Here I do not see SMBus errors - it appears really that i2c device did not respond. OTOH interesting is that there is no timeout. Apparently command completed without setting DONE bit. As I have zero knowledge about hardware I cannot interpret it. Next driver resets SMBus and it works for some time again. Judging by comments in source, it apprently signifies hung ali1535, not external i2c device (it is using KILL, and "this doesn't seem to clear the controller if an external device is hung")